1 \input texinfo @c -*-texinfo-*- vim:tw=72
2 @setfilename regression-test.info
3 @settitle LilyPond Regression test
7 @author Han-Wen Nienhuys and Jan Nieuwenhuizen
8 @title LilyPond Regression test
15 This document tries give a brief overview of LilyPond features. When
16 the text correspond with the shown notation, we consider LilyPond
17 Officially BugFree (tm). This document is intended for finding bugs,
18 and documenting bugfixes.
20 @section Notes and rests
22 Rests. Note that the dot of 8th, 16th and 32nd rests rest should be
23 next to the top of the rest. All rests except the whole rest are
24 centered on the middle staff line.
28 Note head shapes are settable. The stem endings should be adjusted
29 per note head. If you want different note head styles on one stem,
30 you must create a special context called Thread.
32 Harmonic notes have a different shape and different
33 dimensions. Nevertheless, noteheads in both styles can be combined, on
34 either up or down stems.
36 @mudelafile{noteheadstyle.ly}
38 Noteheads can have dots, and rests can too. Augmentation dots should
39 never be printed on a staff line, but rather be shifted vertically. They
40 should go up, but in case of multiple parts, the down stems have down
41 shifted dots. (Wanske p. 186) In case of chords, all dots should be in
42 a column. The dots go along as rests are shifted to avoid collisions.
46 Accidentals work: the second note does not get a sharp. The third and
47 fourth show forced and courtesy accidentals
49 @mudelafile{accidental.ly}
51 Multiple measure rests do not collide with barlines and clefs. They
52 are not expanded when you set @code{Score.skipBars}. Although the
53 multi-measure-rest is a Spanner, minimum distances are set to keep it
54 colliding from barlines.
57 @mudelafile{multi-measure-rest.ly}
59 If @code{Score.skipBars} is set,
60 the signs for four, two, and one measure rest are combined to
61 produce the graphical representation of rests for up to 10 bars.
62 The number of bars will be written above the sign.
64 @mudelafile{mm-rests2.ly}
66 A sharp sign after a double sharp sign, as well as a flat sign
67 after a double flat sign is automatically prepended with a
70 @mudelafile{double-single-acc.ly}
74 Stem tremolos or rolls are tremolo signs that look like beam segments
75 crossing stems. If the stem is in a beam, the tremolo must be parallel
76 to the beam. If the stem is invisible (eg. on a whole note), the
77 tremolo must be centered on the note.
79 @mudelafile{stem-tremolo.ly}
81 Chord tremolos look like beams, but are a kind of repeat symbol.
82 To avoid confusion, chord tremolo beams do not reach the stems, but
83 leave a gap. Chord tremolo beams on half notes are not ambiguous,
84 as half notes cannot appear in a regular beam, and should reach the
87 @mudelafile{chord-tremolo.ly}
89 Beams, stems and noteheads often have communication troubles, since
90 the two systems for y dimensions (1 unit = staffspace, 1 unit = 1
93 Stems, beams, ties and slurs should behave similarly, when placed
94 on the middle staff line. Of course stem-direction is down for high
95 notes, and up for low notes.
97 @mudelafile{stem-direction.ly}
99 Similarly, if @code{stem_default_neutral_direction} is set to @code{-1}.
101 @mudelafile{stem-direction-down.ly}
105 The staccato dot (and all scripts with follow-into-staff set), must
106 not be on staff lines.
108 @mudelafile{staccato-pos.ly}
110 Dynamics appear below or above the staff. If multiple dynamics are
111 linked with (de)crescendi, they should be on the same line.
113 @mudelafile{dyn-line.ly}
117 Chord names are generated from a list pitches, and are customisable
118 from guile. For some unlogical names, guile customisation is used
121 @mudelafile{chord-names.ly}
125 Grace notes are typeset as an encapsulated piece of music. You can
126 have beams, notes, chords, stems etc. within a @code{\grace} section.
127 Slurs that start within a grace section, but aren't ended are attached
128 to the next normal note. Grace notes have zero duration. If there
129 are tuplets, the grace notes won't be under the brace. Grace notes
130 can have accidentals, but they are (currently) spaced at a fixed
131 distance. Grace notes (of course) come before the accidentals of the
132 main note. Grace notes can also be positioned after the main note.
134 Grace notes without beams should have a slash, if @code{flagStyle} is
135 not set. Main note scripts don't end up on the grace note.
137 @mudelafile{grace.ly}
139 @section Beams, slurs and other spanners
141 Beaming is generated automatically. Beams may cross bar lines. In that
142 case, line breaks are forbidden. Yet clef and key signatures are
143 hidden just as with breakable bar lines.
145 @mudelafile{beaming.ly}
147 Beams should behave reasonably well, even under extreme circumstances.
148 Stems may be short, but noteheads should never touch the beam.
150 @mudelafile{beam-extreme.ly}
152 Beams should always reach the middle staff line. The second beam
153 counting from the note head side, should never be lower than the
154 second staff line. This does not hold for grace note beams.
155 Override with @code{noStemExtend}.
157 @mudelafile{beam-position.ly}
159 Slurs should look nice and symmetric. The curvature may increase
160 only to avoid noteheads, and as little as possible. Slurs never
161 run through noteheads or stems.
163 @mudelafile{slur-nice.ly}
164 @mudelafile{slur-symmetry.ly}
165 @mudelafile{slur-symmetry-1.ly}
167 Across line breaks, slurs behave nicely. On the left, they extend to
168 just after the preferatory matter, and on the right to the end of the
169 staff. A slur should follow the same vertical direction it would have
172 @mudelafile{slur-broken-trend.ly}
174 Ties are strictly horizontal. They are placed in between note heads.
175 The horizontal middle should not overlap with a staffline.
179 When tieing chords, the outer slurs point outwards, the inner slurs
180 point away from the center of the staff. Override with
181 @code{tieVerticalDirection}.
183 @mudelafile{tie-chord.ly}
185 When tieing notes with accidentals across a bar boundary, the accidental
186 must not be drawn on the note in the new bar. Instead, the next note of
187 the same pitch in this bar should always show the accidental (even if
188 it's natural). Slurring a accidentaled note to a natural one across bar
189 boundaries should be explicit.
191 Pitches can be verified by printing them with the @code{NoteNames} context.
193 @mudelafile{tie-accidental.ly}
195 Beams can be typeset over fixed distance aligned staffs, beam
196 beautification doesn't really work, but knees do. Beams should be
197 behave well, wherever the switching point is.
199 @mudelafile{beam-cross-staff.ly}
201 The same goes for slurs. They behave decently when broken across
204 @mudelafile{slur-cross-staff.ly}
206 Tuplets are indicated by a bracket with a number. There should be no
207 bracket if there is one beam that matches the length of the tuplet.
208 The bracket does not interfere with the stafflines, and the number is
209 centered in the gap in the bracket.
213 @section Property details
215 More specific settings take precendence over less specific settings. The
216 second slur has slurDirection set to down, overriding the stemup setting.
218 @mudelafile{generic-property-override.ly}
222 LilyPond has three modes for repeats: folded, unfolded and
223 semi-unfolded. Unfolded repeats are fully written out. Semi unfolded
224 repeats have the body written and all alternatives sequentially.
225 Folded repeats have the body written and all alternatives
226 simultaneo.ly. If the number of alternatives is larger than the
227 repeat count, the excess alternatives are ignored. If the number of
228 alternatives is smaller, the first alternative is multiplied to get to
229 the number of repeats.
233 @mudelafile{repeat-unfold.ly}
235 Volta (Semi folded) behavior. Voltas can start on non-barline moments.
236 If they don't barlines should still be shown.
238 @mudelafile{repeat-volta.ly}
240 Folded. This doesn't make sense without alternatives, but it works.
242 @mudelafile{repeat-fold.ly}
244 Across linebreaks, the left edge of a first and second alternative
245 bracket should be equal
247 @mudelafile{repeat-line-break.ly}
253 Lyrics can be set to a melody automatically. Excess lyrics will be
254 dumped. Lyrics will not be set over rests. You can have melismata
255 either by setting a property melismaBusy, or by setting
256 automaticMelismas (which will set melismas during slurs and ties). If
257 you want a different order than first Music, then Lyrics, you must
258 precook a chord of staffs/lyrics and label those. Of course
259 @code{\rhythm} ignores any other rhythms in the piece. Hyphens and
260 extenders do not assume anything about lyric lengths, so they continue
263 @mudelafile{lyric-combine.ly}
265 @section Multiple notes
267 Rests should not collide with beams, stems and noteheads. Rests may
268 be under beams. Rests should be move by integral number of spaces
269 inside the staff, and by half spaces outside. Notice that the half
270 and whole rests just outside the staff get ledger lines in different
273 @mudelafile{rest-collision.ly}
275 Normal collisions. We have support for polyphony, where the
276 middle voices are horizontally shifted.
278 @mudelafile{collisions.ly}
280 The number of stafflines of a staff can be set with the property
281 numberOfStaffLines. Ledger lines both on note heads and rests are
282 adjusted. Barlines also are adjusted.
285 @mudelafile{number-staff-lines.ly}
289 In a limited number of cases, LilyPond corrects for optical spacing
290 effects. In this example, space for opposite pointed stems is adjusted
292 @mudelafile{stem-spacing.ly}
294 If there are accidentals in the music, we add space, but the space
295 between note and accidentals is less than between the notes with the
296 same value. Clef changes also get extra space, but not as much as
299 Even if a line is very tightly spaced, there will still be room
300 between prefatory matter and the following notes. The space after the
301 prefatory is very rigid. In contrast, the space before the barline
302 must stretch like the space within the measure.
306 @mudelafile{spacing-tight.ly}
310 @mudelafile{spacing-natural.ly}
314 @mudelafile{spacing-loose.ly}
316 Adding a @code{Bar_engraver} to the LyricsVoice context makes sure that
317 lyrics don't collide with barlines.
319 @mudelafile{lyrics-bar.ly}
321 Text is set with empty horizontal dimensions. The boolean property
322 textNonEmpty is used to respect the horizontal size of text.
324 @mudelafile{non-empty-text.ly}
326 @section Global stuff
328 Breaks can be encouraged and discouraged using @code{\break} and
329 @code{\nobreak}. They are abbrevs for @code{\penalty} commands.
331 @mudelafile{break.ly}
334 Markings that are attached to (invisible) barlines are
335 delicate: the are attached to the rest of the score without the score
336 knowing it. Consequently, they fall over often.
338 @mudelafile{bar-scripts.ly}
340 Staff margins are also markings attached to barlines. They should be
341 left of the staff, and be centered vertically wrt the staff. They may
342 be on normal staffs, but also on compound staffs, like the PianoStaff
344 @mudelafile{staff-margin.ly}
346 Breathing signs, also used for phrasing, do normally not influence
347 global spacing -- only if space gets tight, notes are shifted to make
348 room for the breathing sign. Breathing signs break beams running
349 through their voice. In the following example, the notes in the first
350 two measures all have the same distance from each other:
352 @mudelafile{breathing-sign.ly}
354 Hara kiri staffs kill themselves if they are empty. This example really
355 contains two staffs, but the second contains only spaces, and is
358 @mudelafile{hara-kiri-short.ly}
360 In orchestral scores and hymns, voices are traditionally combined onto
361 one staff. LilyPond has a part combiner, that combines or separates two
362 voices according to actual rhythm and pitch. User-defined texts such as
363 ``solo'' and ``@`a2'' are typeset automagically, as appropriate.
365 @mudelafile{part-combine.ly}
368 Fonts are available in a default set of sizes: 11, 13, 16, 20, 23 and
369 26pt staffheight. Sizes of the text fonts and symbol fonts are made
370 to match the staff dimensions.
372 @mudelafile[nonfragment]{size11.ly}
374 @mudelafile[nonfragment]{size13.ly}
376 @mudelafile[nonfragment]{size16.ly}
378 @mudelafile[nonfragment]{size20.ly}
380 @mudelafile[nonfragment]{size23.ly}
382 @mudelafile[nonfragment]{size26.ly}
385 @section Clefs and Time Signatures
387 The transparent clef should not occupy any space and with style
388 @code{fullSizeChanges}, the changing clef should be typeset in full
389 size. For octaviated clefs, the ``8'' should appear closely above or
390 below the clef respectively. The ``8'' is processed in a convoluted
391 way, so this is fragile as well.
393 @mudelafile{clefs.ly}
396 Key signatures appear on key changes. They may also
397 appear without barlines. The restoration accidentals are not printed at
398 the start of the line. If @code{createKeyOnClefChange} is set, they're
399 also created on a clef change.
407 @c the input file is too long and does not test for specific bugs
409 By default, time signatures are written with two numbers. With style
410 ``C'', 4/4 and 2/2 are written with their corresponding symbols and
411 with style ``old'', 2/2, 3/2, 2/4, 3/4, 4/4, 6/4, 9/4, 4/8, 6/8 and
412 9/8 are typeset with symbols, all other signatures retain the default
413 layout. The style ``1'', gives single number signatures for all
416 \mu delafile{time.ly}
421 @section Hacks and Features
423 As a last resort, the placement of items can be adjusted manually, by
424 setting the @code{extra-offset} of an output object.
426 @mudelafile{generic-output-property.ly}
428 The same mechanism can be used to force pagebreaks.
430 @mudelafile{between-systems.ly}